Imaging surveillance after open aortic repair: a feasibility study of three-dimensional growth mapping

Abstract

OBJECTIVES Confident growth assessment during imaging follow-up is often limited by substantial variability of diameter measurements and the fact that growth does not always occur at standard measurement locations. There is a need for imaging-based techniques to more accurately assess growth. In this study, we investigated the feasibility of a three-dimensional aortic growth assessment technique to quantify aortic growth in patients following open aortic repair. METHODS Three-dimensional aortic growth was measured using vascular deformation mapping (VDM), a technique which quantifies the localized rate of volumetric growth at the aortic wall, expressed in units of Jacobian (J) per year. We included 16 patients and analysed 6 aortic segments per patient (96 total segments). Growth was assessed by 3 metrics: clinically reported diameters, Jacobian determinant and targeted diameter re-measurements. RESULTS VDM was able to clearly depict the presence or absence of localized aortic growth and allows for an assessment of the distribution of growth and its relation to anatomic landmarks (e.g. anastomoses, branch arteries). Targeted diameter change showed a stronger and significant correlation with J (r = 0.20, P = 0.047) compared to clinical diameter change (r = 0.15, P = 0.141). Among 20/96 (21%) segments with growth identified by VDM, growth was confirmed by clinical measurements in 7 and targeted re-measurements in 11. Agreement of growth assessments between VDM and diameter measurements was slightly higher for targeted re-measurements (kappa = 0.38) compared to clinical measurements (kappa = 0.25). CONCLUSIONS Aortic growth is often uncertain and underappreciated when assessed via standard diameter measurements. Three-dimensional growth assessment with VDM offers a more comprehensive assessment of growth, allows for targeted diameter measurements and could be an additional tool to determine which post-surgical patients at high and low risk for future complications.

Three-dimensional aortic geometry mapping via registration of non-gated contrast-enhanced or gated and respiratory-navigated MR angiographies

“…Given its ability to measure local growth with superior reproducibility, AGM can enhance the capability to detect changes in aortic diameter, thus potentially improving clinical management. Notably, AGM allows to identify the largest diameter and GR at any location, which could be overlooked through manual assessment [11] , [30] potentially underestimating patient risk. Indeed, maximum AscAo and DescAo diameter and GR are rarely located at the level of the pulmonary bifurcation, the standard anatomical reference [11] .…”

Sex-specific Morphometric Analysis of Ascending Aorta and Aortic Arch for Planning Thoracic Endovascular Aortic Repair

“…Endovascular repair of the AA is the final frontier in aortic surgery. The first ascending thoracic endovascular aortic repair (aTEVAR) for type A aortic dissection (TAAD) was reported in 2000 (1)(2)(3). Nowadays, it is more commonly employed in expert aortic centers, mostly to treat patients otherwise not fit for open surgical repair (4,5).…”